Use of the float-moor-crush approach for subtotal mid-segment collapse of a protruding aorto-ostial vein graft stent: a case report

<p>Abstract</p> <p>Introduction</p> <p>Aorto-ostial stenting remains one of the most demanding and risky types of angioplasty to perform. We report a case outlining a creative solution for the reengagement of a protruding aorto-ostial stent.</p> <p>Case presentation</p> <p>A 69-year-old Caucasian man was admitted to our hospital's coronary care unit with progressive unstable angina five years following coronary artery bypass grafting and three years after percutaneous coronary intervention of the graft. Several attempts to engage the protruding part of the aorto-ostial stent in the graft failed. A catheter was eventually floated towards the protruding part using a wire to moor the catheter to the stent through the side-strut. The proximal part of the protruding stent was subsequently crushed with a new stent. Stent patency was observed 12 months after the procedure was performed.</p> <p>Conclusion</p> <p>Although careful cannulation of a aorto-ostial stent during repeat coronary angiography coupled with the placement of a guidewire and stent through the true stent lumen during repeat intervention remains the ideal approach for aorto-ostial in-stent restenosis, this case report confirms the feasibility of the side-strut stenting technique in reaching a long-term positive outcome.</p

The effect of electrical neurostimulation on collateral perfusion during acute coronary occlusion

<p>Abstract</p> <p>Background</p> <p>Electrical neurostimulation can be used to treat patients with refractory angina, it reduces angina and ischemia. Previous data have suggested that electrical neurostimulation may alleviate myocardial ischaemia through increased collateral perfusion. We investigated the effect of electrical neurostimulation on functional collateral perfusion, assessed by distal coronary pressure measurement during acute coronary occlusion. We sought to study the effect of electrical neurostimulation on collateral perfusion.</p> <p>Methods</p> <p>Sixty patients with stable angina and significant coronary artery disease planned for elective percutaneous coronary intervention were split in two groups. In all patients two balloon inflations of 60 seconds were performed, the first for balloon dilatation of the lesion (first episode), the second for stent delivery (second episode). The Pw/Pa ratio (wedge pressure/aortic pressure) was measured during both ischaemic episodes. Group 1 received 5 minutes of active neurostimulation before plus 1 minute during the first episode, group 2 received 5 minutes of active neurostimulation before plus 1 minute during the second episode.</p> <p>Results</p> <p>In group 1 the Pw/Pa ratio decreased by 10 ± 22% from 0.20 ± 0.09 to 0.19 ± 0.09 (p = 0.004) when electrical neurostimulation was deactivated. In group 2 the Pw/Pa ratio increased by 9 ± 15% from 0.22 ± 0.09 to 0.24 ± 0.10 (p = 0.001) when electrical neurostimulation was activated.</p> <p>Conclusion</p> <p>Electrical neurostimulation induces a significant improvement in the Pw/Pa ratio during acute coronary occlusion.</p

Pedestrian activity simulation in shopping environments:an irregular network approach

Micro-scale agent-based modeling can be used for the simulation of pedestrian movement for low and high density scenarios and of the effect of changes in an environment. Such models can also be used for pedestrian dynamics in city centers to show the design effects in the shopping environment. This paper focuses on the generation of the movement network and the underlying behavioral rules that conducts the activation of pedestrians on the network representing a shopping environment. The store visits will be realized by Monte Carlo simulation

Modeling planned and unplanned store stops for the scenario based simulation of pedestrian activity in city centers

Slide presentatio

Generation of User-defined Landscapes for Multi-actor Plan-making

In this paper the functioning of the landscape generator is presented. The landscape generator is developed as part of the planning support system called Simlandscape. Using real-world spatial data and a user-defined intended landscape typology, the landscape generator progresses for satisfying an overall fitness function. This fitness function is compiled of a set of criterion functions describing configurational characteristics of a landscape typology. When the overall fitness function is satisfied a landscape configuration is generated. Discerning technical characteristics with respect to other optimisation techniques, are the use of straightforward design input rules (criterion functions) and its ability to produce acceptable results in considerable time

DDDoolz - A Virtual Reality Sketch Tool for Early Design

This paper presents DDDoolz, a desktop-VR three-dimensional voxel sketchtool. DDDoolz is developed in the Design Systems Group to explore the use of Virtual Reality technology in the early design stage. The aim is to offer a sketch-like environment in VR with an unobtrusive interface. The paper presents DDDoolz, how it is used in education and with partners in architectural practice, and some future developments

Dynamic plan modelling and visualization : converting an urban development plan into a transition scenario

Application of 3D models in urban planning practice is still limited to visualization of existing or newly designed situations. Municipalities are looking for possibilities to communicate the transition process of the urban development area with the citizens. A prototype system was developed to investigate what the technical requirements are of such a tool and what the organizational consequences will be. As an example, screenshots are shown of a district in Eindhoven at different moments in time. Finally, recommendations are given on what is needed to turn the prototype into a professional tool

Methodology to generate landscape configurations for use in multi-actor plan-making processes

In this paper, we investigate an approach to generate landscape configurations for use in multi-actor plan-making processes. Using the information from predefined lot typologies, a heuristic allocation method, consisting of a suitability function and an allocation mechanism of lot components is explained. The suitability function is primarily based on adjacency and distance parameters as found in landscape design literature. The allocation mechanism starts from a random but constrained initial situation, and generates a plausible lot configuration by orderly swapping pairs of cells thereby increasing the overall suitability of the plan . From the results, the limitations of this approach are concluded and the concepts are presented for an improved landscape generation algorithm

Interaction in activity location scheduling

In this paper we discuss the interaction in activity location scheduling which is the main subject of an ongoing research project called User Simulation of Space Utilization . The aim of this research project is to develop an overall model for the simulation of human movement and utilization of space capacity in office buildings. In our model, two aspects are essential: the interaction between the building occupants while performing their activities and the way to model these activities in space